In a conventional fluid cylinder, a piston rod extends through an opening in the end of the cylinder and a packing gland is utilized to provide a seal to the sliding piston rod. Various types of packing glands have been employed in the past and the typical packing gland is complex in structure and is relatively costly.
U.S. Pat. No. 2,639,198 describes a packing gland formed of a resilient material reinforced with fabric. The seal is contained within a recess in an end cap of the cylinder and the inner end of the seal engages a shoulder on the cylinder end cap, while the outer end the seal is engaged by a snap ring. The inner end of the seal in U.S. Pat. No. 2,639,198 is provided with an annular flexible lip which is sealingly engaged with the piston rod while the outer end of the seal is formed with a tapered wiper member that rides along the piston rod.
U.S. Pat. No. 3,812,938 relates to a packing gland construction for a vehicle shock absorber. In the construction of this patent, the packing gland consists of three separate resilient members including a generally cylindrical sealing sleeve, an annular sealing member located inwardly of the sleeve which is retained within an end cap of the cylinder by a retaining ring and a separate resilient wiper member located axially outward of the sealing sleeve and which is retained within a recess in the end cap by a cup-shaped housing.